Truck comprising tractor and semi-trailer

ABSTRACT

A vehicular assembly comprising a tractor and a semitrailer so detachably coupled together that they act as a unit, wherein the assembly has three zones of support, one of which is provided by a zero rate suspension means and the other two of which are provided by variable rate suspension means, whereby to maintain reasonably constant a desired pattern of load distribution between the three zones.

United States Patent 1 Self et a1.

[ 1 Feb. 27, 1973 154] TRUCK COMPRISING TRACTOR AND SEMI-TRAILER [75Inventors: Kenneth W. Sell, Norman B. Chew, both of Lake Oswego, Oreg.:Bill I. Twyman, Vancouver, Wash.

[73] Assignee: Freightliner Corporation, Portland.

Oreg.

22 Filed: Aug. 27, 1970 21 Appl. No.: 67,398

[52] US. Cl. ..280/415 B, 280/407, 280/423 R, 280/150.5, 280/124 F,280/D1G. l, 180/14 R, 280/408 [51] Int. Cl. ..B62d 53/00 [58] Field ofSearch...280/423 R, 415 B, 405 A, 407, 280/124 F; 180/12, 89

[5 6] References Cited UNITED STATES PATENTS 3,104,679 8/1963 Gouirand..280/124 F X 10/1963 Rittenhouse ..280/423 R X 3,237,966 3/1966 Ayers..280/423 R X 3,411,600 11/1968 Loving et a1...... ..180/12X 3,542,41411/1970 Nelson.... ..280/423 R X 3,586,119 6/1971 Chuchua et a1 ..180/12X FOREIGN PATENTS OR APPLICATIONS 1,027,996 4/1958 Germany ..280/405 APrimary Examiner-Leo Friaglia Attorney-Buckhorn, Blore, Kla'rquist andSparkman [57] ABSTRACT A vehicular assembly comprising a tractor and asemitrailer so detachably coupled together that they act as a unit,wherein the assembly has three zones of support, one of which isprovided by a zero rate suspension means and the other two of which areprovided by variable rate suspension means, whereby to maintainreasonably constant a desired pattern of load distribution between thethree zones.

11 Claims, 10 Drawing Figures PAW-INIEB Z 3.118.346

SHEET 10F 4 INVENTORS.

BUCKHORN, BLORE, KLARQUIST 8 SPARKMAN ATTORNEYS PYXTENTEU 3.718.346

SHEET 2 0F 4 BUCKHORN, BLORE, KLARQUIST & SPARKMAN ATTORNEYS PATENTED 3,7 1 8.346

SHEET 3 BF 4 KENNETH Wv SE1. NORMAN B.CHE 4o "BILL 1. TWYMAN INVENTORS.

BUCKHORN, BLORE, KLARQUIST & SPARKMAN ATTORNEYS PATENTEDFEBZYIBU3.718.346

sumuum FIG. 9

KENNETH W. SELF NORMAN B. CHEW BILL I. TWYMAN INVENTORS.

BUCKHORN, BLORE, KLARQUIST & SPARKMAN ATTORNEYS TRUCK COMPRISING TRACTORAND SEMI- TRAILER DESCRIPTION This invention relates to a truckcomprising a tractor and semitrailer, and more particularly to improvedstructure for rigidly locking together a tractor and a semitrailer.

An object of the invention is to provide a truck separable into atractor and semitrailer.

Another object of the invention is to provide new and improved structurefor rigidly locking together a tractor and a trailer.

A further object of the invention is to provide a tractor having a fifthwheel which is slidable between a rear, coupling position and a forward,running position and a frame serving as a guideway for a guide on atrailer frame and having a horizontal alignment socket therein adaptedto receive a pin on the trailer frame.

Another object of the invention is to provide a trailer having a frameprovided with a fixed kingpin adapted to be secured to a fifth wheelslidable on a tractor between a rear, coupling position and a forward,running position and the trailer frame also being provided with guidesadapted to bracket the tractor frame to maintain horizontal alignmentbetween the tractor and trailer frames.

Another object of the invention is to provide a combination in which atrailer frame attachable to a trailer body has a fixed kingpin, a pairof fixed vertically depending guides and a fixed locking pin.

Another object of the invention is to provide a tractor and a trailerwhich can be locked rigidly together and in which the only movable partsof the structure locking the tractor and the trailer together is amovable fifth wheel on the tractor.

Another object of the invention is to provide a tractor and a trailerlocked together to form a truck and adapted to adjustably distributeloads over the several axles of the truck.

Another object of the invention is to provide a tractor adapted tocouple hingedly to a trailer structure for operating therewith in atrailer mode of operation and, alternately, to lock to the trailer atpoints near the forward end of a container of the trailer and near therear end of the container for operating therewith in a truck mode ofoperation.

A further object of the invention is to provide a tractor having a driveaxle supporting a pair of air springs, self-levelers and control meansselectively operable to connect the self-levelers to the air springs fora trailer mode of operation and to cut out the air springs to provide afloating drive axle for a truck mode of operation.

Another object of the invention is to provide a tractor having a frame,front coupler means and a guideway extending along the frame for guidinga coupler means on a trailer along the guideway to the front couplermeans.

Another object of the invention is to provide a tractor-trailercombination having on the tractor front steerable wheeled axle means anda rear wheeled drive axle and also having on the trailer a wheeledtrailer axle spaced from the drive axle a distance relative to thedistance between the front axle means and the drive axle means such thatoptimum steering and load distribution are provided.

Another object of the invention is to provide a trailer structure havinghinged landing gear legs adapted to at least partially fold up into arecess in the bottom of a container to provide clearance for wheels of atractor when the trailer structure is secured to the tractor to form atruck therewith and in a position in which the legs are positioned overthe wheels of the tractor.

Another object of the invention is to provide a trailer structure havingclip-on trailer suspension means detachably connected to the rear endportion of a container, clip-on landing gear detachably connected to thecentral portion of the container and clip-on front coupler meansdetachably connected to the front end portion of the container, thetrailer suspension means being provided with a socket for receiving andinterlocking with the rear end portion of a tractor frame.

In the drawings:

FIG. 1 is a top plan view of an improved truck combination forming oneembodiment of the invention;

FIG. 2 is a side elevation view of the truck combination of FIG. 1;

FIG. 3 is an enlarged, vertical sectional view taken along line 33 ofFIG. 1;

FIG. 4 is an enlarged, horizontal sectional view taken along line 44 ofFIG. 3;

FIG. 5 is an enlarged, vertical sectional view taken along line 5-5 ofFIG. 4;

FIG. 6 is an enlarged vertical sectional view taken along line 6-6 ofFIG. 1;

FIG. 7 is an enlarged fragmentary, vertical sectional view taken alongline 7-7 of FIG. 2;

FIG. 8 is a diagrammatic view of an air suspension system of the truckcombination of FIG. 1;

FIG. 9 is a side elevation view of a truck combination forming analternate embodiment of the invention; and

FIG. 10 is a fragmentary horizontal sectional view of the truckcombination of FIG. 9.

Referring now in detail to the drawings, there is shown therein animproved truck combination forming one embodiment of the invention andincluding a tractor l0 and semi-trailer 12 having a container of body13. The trailer has a kingpin 14 rigidly secured in a fixed position tothe forward end of a conventional bottom frame 16 of the trailer and isadapted to be connected to a fifth wheel 18 of the tractor when thefifth wheel is in its rear position on tractor frame 20, as shown inbroken lines in FIGS. 1 and 2. A releasable latch 22 is provided forsecuring the kingpin to the fifth wheel in the usual manner.

With the trailer so connected to the fifth wheel, a truck-trailercombination can be used as a semi with the trailer articulated to thetractor. Alternately, when desired, with the trailer and tractor socoupled together, latch actuator 23 (FIG. 6) is actuated to release aslide 25, the tractor is backed up to slide a fifth wheel mounting baseor slide 25 relatively forwardly along parallel, longitudinal guideportions 24 on a supporting plate 27 fixed to the tractor frame to theforward position of the fifth wheel which is shown in full lines inFIGS. 1 and 2, the plate 27 having hold down rails 31. As the tractor isso backed up, the tractor frame 20 moves in between side guides 26 of anadapter frame or socket device 28 of the trailer and over a locking pinor retainer 30 (FIGS. 3 and 4) on the frame 28. The trailer and tractornow are locked rigidly together and can be used as a fixed body truck.The trailer also is provided with a coupling 32 (FIGS. 1 and 2) forcoupling to another, also full lengthed trailer (not shown) which may beeither conventional or like the trailer 12 for operation as a fixed bodytruck with the second full lengthed trailer coupled thereto.

The tractor frame 20 is a rigid, generally boxlike frame supported byknown air suspension bags 40 (FIGS. 3 and carried by known rear axlesuspension structure 42 suspending a conventional wheeled rear drive andaxle construction 43 having a drive axle 45. The fifth wheel 18 ismounted on the base 25 (FIG. 6) which has slide members 46 slidablealong the guide portions 24. The slide members 46 carry locking dogs 48of the latch 23. The dogs 48 are selectively actuated to lock the slideto rear tooth segments 53 (FIG. 1) fixed to the rear portion of theguideway 27 (FIG. 6) of the tractor frame 20. The latch 23 may beselectively actuated from cab 84 of the tractor to release the slide 25from the rear ones of the segments 53 to permit the slide to be slidfrom its rear position to its forward position. The latch 23 then isactuated to lock the dogs 48 to front toothed segments 53 to rigidlylock the slide in its forward position. Stop members (not shown) areprovided on the guideway 27 to limit the sliding movement of the slideto between the rear and the forward positions thereof. The toothedsegments lock the fifth wheel either in its rear position, for instance,about 8 percent of the length of the tractor wheelbase ahead of thedrive axle 43 for standard trailer operation, or ahead of the drivingaxle, for instance, about 65 percent of the length of the tractorwheelbase, for integral truck mode of operation.

The adapter frame 28 includes longitudinal members 60 (FIGS. 2 and 3)welded to the trailer frame or bed 16, a tubular box section 62 andchannel-like gussets 64 (FIG. 5) which are welded to the members 60, theplate-like side guides 26 and to the bed 16. Outwardly and forwardlyinclined entrance wings 68 (FIG. 5) of the guides 26 and welded to thebottoms of the members 60 are reinforced by gussets 70 (FIG. 4) weldedto the wings 68 and the rear portion side guides 26. Upwardly andforwardly inclined guide ramp 72 (FIG. 3) is adapted to slide up overthe end of the tractor frame to vertically align the pin 30 with bore orsocket 74 in the tractor frame 20. The ramp 72 is bolted to stringer 76of the trailer frame 16 and gussets 78 are welded to the frame 16, theramp 72 and the box section 62. The pin 30 is in a horizontal positionand is welded to a transverse angle member 80 welded at its ends to themembers 60 and to the bottom of box section 62.

Front wall 82 (FIGS. 1 and 2) of the container portion 13 fits up closeto the back of a cab 84 of the tractor and has a recess 86 thereinproviding clearance for equipment 88 often mounted on the back of thecab. Suitable electrical cords 90 and air hoses 92 are of lengthssufficient to reach connectors on the trailer when the trailer is in itsrear position. The cables and hoses are retracted by a spring (notshown) within the recess 86 when the trailer is moved to its forwardposition. A conventional steel spring trailer suspension 94 is mountedon the adapter frame 28 of the trailer, and is supported by wheeledtrailer axle 96.

The tractor 10 and the trailer 12 can be used in a trailer mode ofoperation together with the fifth wheel 18 in its rear position. Withthe fifth wheel in its forward position and the adapter frame 28 of thetrailer interlocked with the tractor frame 20, the tractor and trailercan be used as in integral truck-trailer combination. Often, in fleetoperations, there are several trailers 12 for one tractor 10 to form anoperating group and, since each trailer 12 is not appreciably moreexpensive to construct than a conventional trailer, cost is minimized.Each trailer 12 can be used with conventional tractors and each tractor10 can be used with conventional trailers. Also, another conventionaltrailer can be hooked onto the trailer 12 for operation of the tractorl0 and trailer 12 as an integral truck with the conventional trailer oras a two-trailer set up. Thus, great flexibility in the use of thetruck-trailer combination is afforded. In the integral truck mode ofoperation, the container 13 is supported by a three point or zonesuspension, the front point being the fifth wheel 18, the intermediatepoint being the box section 62 and the rear point being the trailersuspension 94.

In-and-out folding landing gear (FIGS. 2 and 7) includes two long pianohinges 102, which are rigidly secured to the side rails or sills of thebed of the container portion 13, and also includes known extensiblebraced legs 104 having feet 106. The hinges 102 mount the legs inpositions slightly offset from each other and in which the legs, when intheir folded positions, move into recesses between stringers 108 of thecontainer portion 13. This recessing of the legs into the recesses inthe bottom of the container portion provides clearance for the legs tomove over the wheels of the drive axle 45.

The air bags 40 (FIGS. 1, 2 and 8) for the integral truck orclose-coupled mode of operation (with the fifth wheel 18 in its forwardposition) are cut off from both air intake and air exhaust so that theyprovide a floating axle suspension from the drive axle 45 to the rearend portion of the tractor frame 20. By floating as applied to thesuspension, it is meant a long throw zero or very low rate spring actionproviding a nearly constant support to the box section 62. For theintegral truck mode of operation, it is necessary that one of the threesuspensions be floating, the drive axle being floated in the embodimentdisclosed herein. For semitrailer operation of the tractor 10 with thetrailer 12 or a conventional trailer with the fifth wheel in its rearposition, known self-leveling valves 116 are connected to the air bagsand control their pressures. When the fifth wheel is in its rearposition, the slide 25 is in a position actuating a normally closedposition or limit valve 1 10 on the tractor frame 20 to its openposition. Air under pressure from a source 111 of air under pressure onthe tractor then is supplied to a normally open valve 1 12 and tonormally closed valves 1 14. This actuates the valve 1 12 to close offair from a line 115, and actuates the valves 114 to open lines 117 ofair under pressure from the self-leveling valves 116. This actuatesshuttle valves 122 to close ports from the valve 1 12 and to open portsof the valves 122 from the valves 114, and air under pressure from thevalves 116 flows through the valves 122 and through valves to the airbags 40. The air bags then are controlled by the selfleveling valves 1l6.

Just before the tractor is backed up to move the fifth wheel 18 to itsforward or close-coupled position, a valve 128 in the cab of the tractoris actuated manually to actuate the actuator 23 to unlatch the fifthwheel slide 25. The tractor then is so backed up, and this releases theswitch 110 which closes. This opens the valves 112 and 122 and closesthe valves 114 to cut out the self-leveling valves 116. The actuation ofthe valve 128 in the cab of the tractor also actuates the valve 120 toopen the air bags 40 to exhaust. Then, when the fifth wheel reaches itsforward or close-coupled position, the driver moves the valve 128 to itsopen position to cause the actuator 23 to lock the fifth wheel slide 25in its forward position and to actuate the valve 120 to close offexhaust from the air bags 40 and connect the air bags to a manuallyadjustable pressure reducing valve 118, which connects the air bags tothe source 111 and supplies the air bags with fixed quantities of air,which quantities can be varied by manual adjustment of the valve 118which is in the cab of the tractor for convenient adjustment by thedriver. The driver adjusts the valve 118 to place the desireddistribution of load between front axle 131, which forms a part of aconventional front axle suspension, the trailer axle 96 and the axle 45,which is the floating axle, to maintain all the wheels on the groundwith substantially constant pressure regardless of uneveness of terrain.A protection valve 147 and a reducing valve 149 are provided in line151. To provide optimum load distribution while also providing goodsteering responsiveness, it has been found that the distance between theaxles 45 and 96 should not be much less than 31 percent and not muchover 41 percent of the distance between the axles 96 and 131, an optimumdistance between the axles 45 and 96 being about 36 percent of theoverall distance between the axles 96 and 131. To aid in turning andprovide desired clearance, the side guides may be spaced outwardlysomewhat from the tractor frame to permit a slight swinging of thetrailer on the kingpin, a total clearance of both sides of aboutone-quarter of an inch having been provided in one constructedembodiment.

EMBODIMENT OF FIGS. 9 AND 10 A truck combination forming an alternateembodiment of the invention shown in FIGS. 9 and 10 includes a tractor210 and a trailer 212. The trailer 212 is like the trailer 12 but has acontainer 213 of the type carried by cargo ships, and the container hasdetachably secured thereto a clip-on kingpin or coupling device 214, aslip-on trailer frame 228 and a clip-on landing gear 201, all of whichare mounted for quick attachment to and detachment from the container213. The trailer frame 228 is supported by a wheeled spring suspension221 including a wheeled rear axle 223. The

tractor 210 is like the tractor 10 except that the tractor- 210 has nomovable fifth wheel structure and instead has a fixed, slotted guideway230 mounted on frame 220 thereof and has a coupler or lock 232 mountedat the front end of slot 233 in the guideway 230. The tractor 210 hasair bags 240 like the air bags 40, the quantities of air in which areadjustably set initially to provide the floating axle suspension and toeffect the desired load distribution. To couple the trailer to thetractor, the tractor is backed up with the pin 214 in the slot 233 toslide the guideway 230 along the pin 214. When the close coupledposition is reached, the coupler 232 is actuated to lock to the pin 214and socket structure of the trailer frame 228 like that of the adapterframe 28 moves over and interlocks with the tractor frame, The pin 214,as shown, is rigidly fixed to the container but could be foldable intothe recess in the bottom of the container if desired. If desired, afifth wheel could be provided in a fixed location at the rear end of thetractor frame to permit semitrailer operation.

In an alternate form of construction of the truck combination of FIGS. 9and 10, instead of having the rear drive axle of the tractor 210floating, the air bags 240 are omitted from the tractor 210 and aresubstituted in the trailer for the spring suspension 221 between theframe 228 and the wheeled rear axle 223. The drive axle has a standardspring suspension and the floating axle is the axle 223, which isadjusted to provide the desired load distribution over the three axles.

Air to the air bags on the trailer are connected to lines from controlsand air source on the tractor by quick disconnect connectors mounted onthe trailer frame and the tractor frame in aligned positions such as toautomatically connect together when the tractor and trailer are in theirclose-coupled condition, and to automatically disconnect when thetractor and trailer are separated from their close coupled condition.

What is claimed is:

1. In a trucking structure,

a tractor including a tractor frame and a tractor drive axle meanssupporting the tractor frame near the rear end thereof,

a trailer comprising container means and a trailer suspension unit fixedto the rear end portion of the container means and including frame meansand wheeled rear axle means,

said trailer suspension unit providing a rear load bearing zone,

releasable rear interlocking means fixed to the tractor frame andtrailer for interlocking the rear end portion of the tractor frame andthe trailer to prevent sidewise movement of the trailer relative to thetractor frame,

load bearing structure between the rear tractor frame and trailer toprovide a second and intermediate load bearing zone,

and releasable front coupling means on the tractor frame and the frontend of the trailer for holding the front end of the trailer againstmovement either vertically or horizontally relative to the tractor frameand to provide a forward and third load bearing zone.

2. The trucking structure of claim 1 wherein the rear interlocking meansincludes guideway means on the trailer bracketing the rear end portionof the tractor frame.

3. The trucking structure of claim 2 wherein the guideway means is ofinverted U-shape.

4. The trucking structure of claim 2 including means for limiting upwardmovement of the intermediate portion of the trailer relative to the rearend portion of the tractor frame.

5. The trucking structure of claim 4 wherein the last named meanscomprises a horizontal pin on the trailer frame means and a socket inthe rear end of the tractor frame.

6. The trucking structure of claim 1 wherein the front coupling meanscomprises a kingpin carried by the trailer and a coupler device on thethe tractor frame adapted to interlock with the kingpin.

7. The trucking structure of claim 6 wherein the coupler devicecomprises a fifth wheel unit, means mounting the fifth wheel slidablybetween a rear position at the rear end portion of the tractor frame anda front position at the front end portion of the tractor frame, andmeans for locking the fifth wheel unit in either of said positions.

8. The trucking structure of claim 1 wherein the rear interlocking meanscomprises socket means on the trailer frame means adapted to receive andinterlock with the rear end portion of the tractor frame.

9. In a truck combination,

a tractor having a frame, front steering axle means and floating reardrive axle means spaced at predetermined distance from the frontsteering axle means,

trailer means extending over the frame, secured to the frame at thefront end portion of the trailer means, and resting on the rear endportion of the frame and secured thereto against sidewise movement, andalso including trailer axle means supporting the rear end portion of thetrailer means, the trailer axle means being spaced to the rear of thedrive axle means a second distance of not substantially greater than 41percent of the overall distance between the trailer axle means and thesteering axle means and not substantially less than 31 percent of saidoverall distance. 10. The truck combination of claim 9 wherein saidsecond distance is about 36 percent of said overall distance.

11. The truck combination of claim 9 including air bag means operativelyconnected to the rear drive axle means and said tractor frame,

means for varying the pressure in the air bags to vary load distributionon the axle means.

UNITED STATES PATENT OFFECE CERTIFEQATE GE CQRREQTWN Patent No.3,718,346 Dated February 27, 1973 Inventor s KENNETH W. SELF: NORMAN B.CHEW: BILL I. TWYMAN It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 2, line 43, "of" should be -or-- Column 5, line 53, "slip-onshoulbe -clip-on-- Column 6, line 45, after "rear" insert -end portion ofthe-- Column 7, line 3, omit one "the" before--tractor frame-- In thecited references: Gouirand should be 9/63 Signed and sealed this 3rd dayof July 1973.

(SEAL) Attest:

EDWARD M.FLETQHER,JR. Rene Tegtmeyer Attestlng Officer A ti Commissionerof Patents 7 USCOMM-DC 60376-P69 U.S.IGOVERNMENT PRINTING OFFICE: 1ss9oass-334 F ORM PO-105O (10-69)

1. In a trucking structure, a tractor including a tractor frame and atractor drive axle means supporting the tractor frame near the rear endthereof, a trailer comprising container means and a trailer suspensionunit fixed to the rear end portion of the container means and includingframe means and wheeled rear axle means, said trailer suspension unitproviding a rear load bearing zone, releasable rear interlocking meansfixed to the tractor frame and trailer for interlocking the rear endpoRtion of the tractor frame and the trailer to prevent sidewisemovement of the trailer relative to the tractor frame, load bearingstructure between the rear tractor frame and trailer to provide a secondand intermediate load bearing zone, and releasable front coupling meanson the tractor frame and the front end of the trailer for holding thefront end of the trailer against movement either vertically orhorizontally relative to the tractor frame and to provide a forward andthird load bearing zone.
 2. The trucking structure of claim 1 whereinthe rear interlocking means includes guideway means on the trailerbracketing the rear end portion of the tractor frame.
 3. The truckingstructure of claim 2 wherein the guideway means is of inverted U-shape.4. The trucking structure of claim 2 including means for limiting upwardmovement of the intermediate portion of the trailer relative to the rearend portion of the tractor frame.
 5. The trucking structure of claim 4wherein the last named means comprises a horizontal pin on the trailerframe means and a socket in the rear end of the tractor frame.
 6. Thetrucking structure of claim 1 wherein the front coupling means comprisesa kingpin carried by the trailer and a coupler device on the the tractorframe adapted to interlock with the kingpin.
 7. The trucking structureof claim 6 wherein the coupler device comprises a fifth wheel unit,means mounting the fifth wheel slidably between a rear position at therear end portion of the tractor frame and a front position at the frontend portion of the tractor frame, and means for locking the fifth wheelunit in either of said positions.
 8. The trucking structure of claim 1wherein the rear interlocking means comprises socket means on thetrailer frame means adapted to receive and interlock with the rear endportion of the tractor frame.
 9. In a truck combination, a tractorhaving a frame, front steering axle means and floating rear drive axlemeans spaced a predetermined distance from the front steering axlemeans, trailer means extending over the frame, secured to the frame atthe front end portion of the trailer means, and resting on the rear endportion of the frame and secured thereto against sidewise movement, andalso including trailer axle means supporting the rear end portion of thetrailer means, the trailer axle means being spaced to the rear of thedrive axle means a second distance of not substantially greater than 41percent of the overall distance between the trailer axle means and thesteering axle means and not substantially less than 31 percent of saidoverall distance.
 10. The truck combination of claim 9 wherein saidsecond distance is about 36 percent of said overall distance.
 11. Thetruck combination of claim 9 including air bag means operativelyconnected to the rear drive axle means and said tractor frame, means forvarying the pressure in the air bags to vary load distribution on theaxle means.